When Does Life Begin? Let’s ask the Experts …

Let’s turn to the leading scientific textbooks to find out when life begins. Check it out:

Keith L. Moore, a world-renowned embryologist and author of the best selling textbook: The Developing Human: Clinically Oriented Embryology (10th edition, Philadelphia, PA: Sauders, 2016) states:

“Human development is a continuous process that begins when an oocyte from a female is fertilized by a sperm from a male,” (pg. 1).

“Human development begins at fertilization when a sperm fuses with an oocyte (the woman’s egg) to form a single cell, the zygote (the term for an egg that is fertilized by a sperm). This highly specialized, totipotent cell (capable of giving rise to any cell type) marks the beginning of each of us as a unique individual” (pg. 12).

Let’s check a different scientific textbook:

“Although life is a continuous process, fertilization…is a critical landmark because, under ordinary circumstances, a new, genetically distinct human organism is formed when the chromosomes of the male and female pronuclei blend in the oocyte (female egg).

Human Embryology & Teratology (Ronan R. O’Rahilly and Fabiola Muller [3rd edition, New York: Wiley-Liss 2001], p. 8).

Let’s check another one:

“Development begins with fertilization, the process by which the male gamete, the sperm, and the female gamete, the oocyte, unite to give rise to a zygote.”

Langman’s Medical Embryology (T.W. Sadler, 11th edition, Philadelphia, PA: Lippincott Williams & Wilkins, 2006, p. 13).

The list goes on. We’ll stop here with the text books solely because of redundancy.


National Geographic produced a television program entitled In the Womb in 2005 that showed the development of the unborn child. In the introduction of the program they sum up the scientific knowledge of the beginning of life:

“The two cells gradually and gracefully become one. This is the moment of conception when an individual’s unique set of DNA is created, a human signature that never existed before and will never be repeated.”


The question of when life begins was put to rest in 1981 (April 23 – 24) when a Senate Judiciary Subcommittee held a hearing on the question of when human life begins. A group of internationally renowned geneticists and biologists testified that life begins at conception.

Here’s what the doctors had to say:

Dr. Micheline M. Mathews-Roth, Harvard Medical School, testified with references from over 20 embryology and other medical textbooks that human life began at conception.

“It is incorrect to say that biological data cannot be decisive…It is scientifically correct to say that an individual human life begins at conception.”

“Father of Modern Genetics” Dr. Jerome Lejeune told the lawmakers:

“To accept the fact that after fertilization has taken place a new human has come into being is no longer a matter of taste or opinion … it is plain experimental evidence. Each individual has a very neat beginning, at conception.”

Dr. Hymie Gordon, Professor of Medical Genetics and physician at the prestigious Mayo Clinic, affirmed this consensus:

“I think we can now also say that the question of the beginning of life – when life begins – is no longer a question for theological or philosophical dispute. It is an established scientific fact. Theologians and philosophers may go on to debate the meaning of life or the purpose of life, but it is an established fact that all life, including human life, begins at the moment of conception.”

Dr. McCarthy de Mere, medical doctor and law professor, University of Tennessee, testified:

“The exact moment of the beginning of personhood and of the human body is at the moment of conception.”

Dr. Alfred Bongiovanni, professor of Pediatrics and Obstetrics, University of Pennsylvania School of Medicine, concluded:

“I am no more prepared to say that these early stages represent an incomplete human being than I would be to say that the child prior to the dramatic effects of puberty … is not a human being. … I have learned from my earliest medical education that human life begins at the time of conception.”

Dr. Landrum Shettles, sometimes called the “Father of In Vitro Fertilization,” notes:

“Conception confers life and makes that life one of a kind.”

The official Senate report reached this conclusion:

“Physicians, biologists, and other scientists agree that conception marks the beginning of the life of a human being – a being that is alive and is a member of the human species. There is overwhelming agreement on this point in countless medical, biological, and scientific writings.”


Planned Parenthood Federation of America, the largest abortion provider in America published a pamphlet in 1963 entitled Plan Your Children for Health and Happiness. The pamphlet stated, “An abortion requires an operation. It kills the life of a baby after it has begun.” Planned Parenthood now rejects that life begins at conception.


Even the definition of “fetus” according to Merriam-Webster Dictionary further explains the science behind when life begins:

Fetus / noun / fe ·tus / ˈfē-təs\: a human being or animal in the later stages of development before it is born.

In Latin, “fetus” means “offspring.”